<b-button type="primary">Open Modal</b-button>

<b-modal title="I am a Modal~">
  <div style="padding: 30px 20px; border: 1px dashed #ccc">
    <div style="height: 200vh">往下滚动试试~👇🏻👇👇🏻👇👇🏻👇</div>
    <span>Hi~ o(*￣▽￣*)ブ</span>
  </div>
</b-modal>

<script>
  const button = document.querySelector('b-button');
  const modal = document.querySelector('b-modal');

  button.addEventListener('click', () => {
    modal.open = true;
  });

  modal.addEventListener('ok', () => {
    modal.open = false;
    window.BMessage.success({ content: "OK~" })
  });

  modal.addEventListener('cancel', () => {
    modal.open = false;
  });
</script>